Various theories have been proposed with respect to a cause of ulcer in human. In particular, it has been elucidated that stress, taking of non-steroidal anti-inflammatory drugs for curing rheumatic diseases, and the like are closely related to ulcer formation, mainly due to relatively excess gastric acid secretion. Accordingly, it is important to suppress the acid secretion in order to prevent ulcer formation and to cure it.
Though various kinds of medicaments for curing ulcer have been conventionally developed, few medicaments have been known to have an effect for preventing stress ulcers from generating.